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Topic Review (Newest First)

11-07-2013 09:37 AM

1971BB427

The coolant level only needs to be high enough to cover the end of the hose. It will fill and return as the system heats and cools, but only to the pickup hose level. Even on my catch cans I leave a small amount of coolant inside to make them work as a recovery tank. In mine the hose is within an inch of the bottom, so that's all I need. I have petcocks on both of mine, so I can drain any excess that might not return to the system after it cools.

11-07-2013 09:02 AM

potvinguy

Fill the tank with water. When the radiator overflows into the tank, the excess will drain from the tank.

Look in the tank after the engine has cooled. If the tank is empty, it is too small and the radiator is sucking air. Get a bigger tank. Or not. Some air in the system is not a big deal unless you are really marginal on cooling.

11-06-2013 01:57 PM

ogre

Quote:

Originally Posted by ogre

if i remember correctly... in spite of my crs
3'' diameter ss exhaust tube x 14'' long holds roughly 100 oz of fluid.
not sure it's ever been full of coolant.

my bad... 100 cubic inches = 54 oz

11-06-2013 12:29 PM

AJL Electronics

As others have said, the end of the hose needs to be covered by coolant when cold. As the coolant expands, it will fill the catch tank, any excess being lost to the ground. As the engine cools, it draws back as much coolant as is required to replace the air dispelled. If the level drops too low in the catch tank, you will draw more air into the radiator, which is not what you need in there!

11-06-2013 10:07 AM

sunsetdart

Any recovery tank is basically an expansion tank. It is a place to have coolant expand to after you shut off the motor. You leave it empty and then when the motor is shut off after getting to operating temp,the coolant will push into the tank and then when the motor cools down, a vacuum forms and allows the coolant to flow back to the radiator to keep it at proper level.

11-04-2013 06:37 PM

ogre

if i remember correctly... in spite of my crs
3'' diameter ss exhaust tube x 14'' long holds roughly 100 oz of fluid.
not sure it's ever been full of coolant.

11-03-2013 10:31 AM

bentwings

I have one of these on my Willys. At first I just filled the radiator and ran the motor untill the thermostat opened then installed the radiator cap. Then I filled the coolant recovery tank. The idea being the system would pump out any excess then seek its own level.

As the motor ran up to operating everything worked fine and the tank was about 2 inches from the bottom when cold.

Then as cruises got longer and days got hotter I began running the AC more, the day came when things got very hot. what happened was the coolant expands and pumps out more than the recovery tank can handle and eventually you are low on coolant.

To remedy this I made a 2 qt. pocket tank. It looks like a big hip flask. I attached this in the lower part of the fenderwell and hooked it up to the overflow of the recovery tank. Now I just keep adding a bit of coolant to the recovery tank untill it seeks a constant level.

What it boils down to is I think these tall skinny tanks are just too small. take a look at your CRT on your everyday car or truck. They are much larger often for a smaller motor.

Do the math PI x r* x lg. divide 231 by the result and you get how many qts your recovery system has. I have a little over 3 qts and use all of it.
My truck has almost 2 gallons.

I think the 3 in dia tank is better to start with as it has 2 qt capacity. Even at this it is still marginal....IMHO.

11-03-2013 09:26 AM

ogre

if you can weld, mine was almost free.
one foot of exhaust tubing, with pieces of flattened tubing for the ends.

quote : i just fill the radiator to the top when the coolant is cool, any radiator that is full will burp fluid out as it gets warm.
when the engine warms up it will burp out any expansion fluid and when it cools down it should suck everything back into the tank.

this is how I did mine, it works.

10-04-2013 10:58 AM

Irelands child

This one works just fine. It doesn't hold any water but what is pushed into it by the radiator cap popping then is returned to the radiator via vacuum as the engine cools. I have it mounted on the opposite side of the radiator now, since I changed the fuel line and installed a new FP regulator but it's still operating correctly regardless of where installed:

10-04-2013 10:06 AM

ogre

i consider those 2'' diameter tanks more of a puke tank than an actual coolant recovery/fill tank
i made mine out of 3'' ss exhaust tubing about 14'' long with no way to check the level. it holds about 1.5 quarts.
i just fill the radiator to the top when the coolant is cool, any radiator that is full will burp fluid out as it gets warm.
when the engine warms up it will burp out any expansion fluid and when it cools down it should suck everything back into the tank.
i'm under my hood often enough to keep an eye on the radiator level

3'' 304 ss tube. capped on both ends. fill drain fitting near bottom. vent tube welded in bottom is cut at an angle and run to the top of the tank.

10-04-2013 08:28 AM

RWENUTS

If you leave it an inch from the top and use a recovery tank the level in the rad will slowly go down and eventually you'll start running hot.
Put enough fluid in the recovery tank to cover the hose end by 2 inches, fill the rad to the top and run it. After the first cool down check and maintain the level in the tank.
Or just set it up the old way a couple inches down and use the tank as a catch can.
How do the tanks on your original rad like the pressure? THey weren't made for even 7 lbs.

10-04-2013 01:43 AM

rustman

So how come I didn't get any stinking instruction? Thanks very much for posting them. Actually I did get a one page showing which tube to hook your overflow tube to but it said nothing about how much coolant to have in the recovery tank or to leave it empty. I think it should have some to make sure you don't end up with air being drawn back into the radiator. If that happens, when you release the cap you have coolant spilling out.
If I didn't say so before I have the original 36 Ford radiator re-plumbed for the 350 Chevy which is suppose to have 450 hp. and it has A/C. So far I am amazed at what a great job this radiator does (knock on wood. I took it to a neighboring town this summer and it was in the mid 90's and with the a/c on it got up to a little over 200 degrees. I checked it with an infrared gun and the gauge is pretty accurate. I have a 180 degree thermostat in it. I need to check it since it seems to take quite awhile for it to get up to temperature. I am thinking that maybe it is not completely closing when cool. Anyway, thanks very much for all the input. I will try draining all but 16 OZ out of the recovery tank and give it a try. I think I will go back to the way we used to do it and leave the upper tank level about an inch from the top.

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